GmatKiss wrote:Some of the tenth-century stave churches of Norway are still standing, demonstrating that with sound design and maintenance, wooden buildings can last indefinitely.

(A) standing, demonstrating that with sound design and maintenance, wooden buildings can last indefinitely (Prepositional phrase clearly modifies builings; 'phrase 'demonstrating...' modifies previous clause and give additional information about the chruches / builings in general)
(D) standing, and they demonstrate wooden buildings can last indefinitely when there is sound design and maintenance (bold part implies 'chruches demonstrate buildings. But the fact is 'standing of chruches till today' together demonstratate 'wooden building can last....'. Moreover, 'there is...' is wordy)
(E) standing, and they demonstrate how a wooden building can last indefinitely when it has sound design and maintenance (they demonstrate as described in D; moreover, use of adverbial clause 'when it...' suggests, When a building has sound design and maintenance, a wooden building can last indefinitely. It also replaces 'buildings' with 'a building' for no good reason)

OA after sometime

GmatKiss wrote:OA is [spoiler]A. Bang on![/spoiler]

GmatKiss wrote:Some of the tenth-century stave churches of Norway are still standing, demonstrating that with sound design and maintenance, wooden buildings can last indefinitely.

(A) standing, demonstrating that with sound design and maintenance, wooden buildings can last indefinitely
(D) standing, and they demonstrate wooden buildings can last indefinitely when there is sound design and maintenance
(E) standing, and they demonstrate how a wooden building can last indefinitely when it has sound design and maintenance

OA after sometime

GmatKiss wrote:Some of the tenth-century stave churches of Norway are still standing, demonstrating that with sound design and maintenance, wooden buildings can last indefinitely.

(A) standing, demonstrating that with sound design and maintenance, wooden buildings can last indefinitely
(D) standing, and they demonstrate wooden buildings can last indefinitely when there is sound design and maintenance ---- changes the intended meaning of the sentence
(E) standing, and they demonstrate how a wooden building can last indefinitely when it has sound design and maintenance ---- changes the intended meaning of the sentence

OA after sometime